One to one-and-a-half inches of spray polyurethane foam, seamless, at R-6.5–7 per inch, under a white reflective coat. It is why flat-roof Phoenix homes have used foam since the 1970s — and why most new foam roofs go over the old roof without a tear-off.
| Scope | Published rate | 2,000 sq ft |
|---|---|---|
| Foam overlay on sound existing roof | $3.50–$7 (Arizona Roof Co) · $5–$9 (Durafoam) | $7,000–$18,000 |
| Replacement with tear-off of old BUR/foam | $10–$15 (Travek) | $20,000–$30,000 |
Drag to your roof size. The bands are the published per-square-foot rates above, not our pricing.
Tip: a typical single-story Phoenix flat roof is 1,600–2,400 sq ft. Measure the footprint on the Maricopa County Assessor parcel map and add 5% for parapets.
The existing roof is dry, sound and not already two layers deep. Foam bonds to it, adds slope to kill ponding, and avoids disposal cost.
Saturated insulation or foam, rotted deck, or a city limit on roof layers. Costs 2–3× but you start clean. A core sample decides it.
A full roof replacement requires a building permit in Phoenix ($135–$720 depending on project value); minor repairs don't. Overlay installs are treated as re-roofs by most Valley cities. The contractor pulls it; make sure the quote says so. Only a ROC-licensed contractor can pull a permit.
Durafoam reports a 15–35% drop in cooling costs after switching from tile or shingle to foam. Put in a summer bill and pick where you think your home lands.
Assumes cooling is ~60% of a Phoenix summer bill (APS and SRP both put summer cooling between half and two-thirds of usage). Savings vary with attic insulation, duct condition and the roof you're replacing. Recoating an existing foam roof restores reflectivity but does not add the full step-change.
Typically 1 to 1.5 inches of closed-cell polyurethane foam at R-6.5–7 per inch, plus a 20–30 mil elastomeric or silicone top coat.
Over a flat or low-slope roof, yes — foam goes over built-up, modified bitumen and old foam. Over pitched tile or shingle it is not the right product; those roofs get underlayment replacement instead.
One to three days for a typical home, weather permitting. Foam cures in minutes; the coating needs dry conditions, which is why April–June and October–November are the install seasons.
Full roof replacement requires a Phoenix building permit; fees run $135–$720 by project value. The licensed contractor pulls it.
LAST REVIEWED 2026-11-01 · Prices on this site are published Valley rates and estimates, not a quote.